PayPal transaction processed but no subscription

We have a few recent issues where PayPal was processed (showing it was for one of our plans), but no subscription was added or renewed. How can this happen and how can we prevent it?

I have the PayPal transaction numbers, but cannot find a payment, a payment basket, nor a history for these payments. There are about 10 over the last week.

Can you please help?

People are still getting the PayPal IPv6 error, but those payments seem to go through, but would it cause this to happen?

That usually means the PayPal IPN never arrived at your site. What PayPal gateway are you using? Standard, Advanced, or Pro? Within CBSubs > Notifications ensure you're seeing IPNs logged for PayPal (notifications of PDT type are just site returns).

IPN Amount/item mismatch / Fraud attempt
receiver_email mismatch: parametered business (2xxxxx) or receiver (kixxxx@rexxxxx) expected does not match IPN business (sxxx@xxx.org) or receiver (sxxx@xxx.org)

is that coming from CB SUBS or PayPal? Both emails are set up and accepted on the PP account so it should not mark as fraud.

I updated the paypal advanced to have the (sxxx@xxx.org) email now, so hopefully this all matches up and the ipn will work properly. Do you think that was the issue?

I updated the paypal advanced to have the (sxxx@xxx.org) email now, so hopefully this all matches up and the ipn will work properly. Do you think that was the issue?

Yes, that was the issue. The email address marked as Primary at PayPal is always the receiver email address and is what should be set in PayPal gateways.